128 KIYOYASU MARUI 



The embrj^ological study of the nervous system supported this 

 idea, inasmuch as it was beUeved that the growth of the axis- 

 cyhnder from the cell-body of an embryonic ganglion cell could 

 be pursued for some distance. Waldeyer (9) summed up all 

 the facts obtained by means of the Golgi technic in 1891 and 

 formulated the 'neurone theory,' in which he took for granted 

 that the nervous system is composed of numerous nerve ele- 

 ments, which are independent anatomically as well as geneti- 

 cally. This theory implied the so-called 'contact theory;' ac- 

 cording to the latter, the telodendrion of the neurone terminates 

 with free endings and the conduction of a stimulus from one 

 neurone to another takes place by means of contact between 

 the nerve endings and the nerve cells. 



Apathy (9), who demonstrated by his own method the neuro- 

 fibrils in clear and sharp pictures, assumed that the neurofibrils 

 at certain points of the central nervous system cross the border 

 of the nerve cell and through abundant splitting and anastomoses 

 with the neurofibrils from the adjacent nerve cells form a real 

 net-work ('neuropil'). Bethe (7), who by means of his molyb- 

 den method stained the neurojibrils in the nervous system of the 

 vertebrate, found on the surface of the ganglion cell as well as 

 its dendrites a fine net-work of irregular configuration, which he 

 called 'Golgi's net' in honor of the discoverer. He claimed an 

 analogy of this net structure w^ith the 'neuropil' of Apathy in the 

 invertebrate, and interpreted it as the connecting link between 

 the ganglion cells and the nerve fibers, which come afar from 

 other cells. He claimed to have found that on the one hand 

 the nerve fibers go over to this pericellular net-work with their 

 telodendria and on the other hand the intracellular neurofibrils 

 enter this same net structure. These theories of Apathy and 

 Bethe cannot therefore be harmonized with the 'neurone doc- 

 trine' :'n which the nerve fibers are considered as non-anastomos- 

 ing. It is to be added here that a pericellular net-work con- 

 tinuous with the nerve fibers was described also by Auerbach 

 (2, 3), Semi Meyer (23) (24), and Held (17, 18). But the first 

 two stood on the standpoint of neurone and contact theory, while 



